Bolster control means



Jan. 25, 1955 w. T. ROSSELL 2,700,346

BOLSTER CONTROL MEANS Filed June 28, 1950 3 Sheets-Sheet l 11v ENTOR. /74L/4M 7/: 55274 BY ATTORNEY 1955 w. T. ROSSELL BOLSTER CONTROL MEANS 5Sheets-Sheet 2 Filed June 28, 1950 u IIIII: Ill-ll I INVENTOR.

ATTOR/Vfy Jan. 25, 1955 w. T. ROSSELL BOLSTER CONTROL MEANS 3Sheets-Sheet 3 Ira-3*- Filed June 28, 1950 3 lullllllllflIl/IIIIIIII INVEN TOR.

ATTORNEY United States Patent 2,700,346 BOLSTER CONTROL MEANS William T.Rossell, New York, N. Y., assignor to Transit Research Corporation, NewYork, N. Y., a corporation of New York Application June 28, 1950, SerialNo. 170,755

Claims. Cl. 105-197.2

This invention relates to rail trucks and more particularly to means forsupporting and for snubblng the bolster thereof in the interests ofimproving the quietness and riding quality of the car body supportedthereby.

A bolster is provided on a truck in order to permit motions of the bodyrelative to the frame and axles of the truck. It has lateral swingingmovements which, in ideal form, should be free when the bolster is at ornear its center or static position to avoid the transmission of manysmall vibrations to the body; it should offer resistance to swingingmovements proportionate to the amount of such movement so that themovement in one direction terminates without shock; and there should beonly enough energy left in the supporting means at the end of a swingingmovement to return the'bolster to center position so that the swingingmovement dies out promptly.

With the above requirements in mind it will be apparent that neither asimple form of swing links nor bolster supporting springs will giveadequate control to the movements of the bolster. In recognition of thisfact, hydraulic shock absorbers and various types of snubbingarrangements have been employed but the results have always beenimperfect either because of inability to maintain initial adjustments,or because the devices were inadequate to make the necessary correctionsof bolster operation throughout the operating ranges encountered.

The first object of this invention is to provide spring means forsupporting each end of the bolster and which will serve as the mainspringsfor all vertical movements of the car body with respect to thetruck wheels, and to so arrange and support these springing means thattheir reaction to bolster swinging movements will bear no relation tothe vertical reactions but may be adjusted entirely independentlythereof.

It is then the principal object to provide bolster springing and controlmeans which will offer minimum resistance 1 to swinging of the bolsterat or near its central or static position, which will offer increasingfrictional resistance to increasing swinging movement, and which willimpart small energy to the bolster at the end of its swing in the returndirection.

More specifically it is anobject of this invention to provide springassemblies for supporting each end of the bolster, these assembliesbeing capable of offering increasing resistance to increasing swingingmovement of the bolster. As will be hereinafter explained this objectentails the provision of means for stiffening the action of the springsunder progressively increasing lateral deflection together with meansfor elevating the out-swinging end of the bolster against gravity in themanner of swing links. 7

. Another specific object of the invention is to provide means forpivoting the spring assemblies so that they will tilt or rock, thusdeflecting the bolster from its normal faath of swinging againstfriction pads carried-by the truck rame.

A further object is to provide spring assemblies as above describedwhich may be supplied and mounted in place on the truck as a unit.

Other objects and advantages will become hereinafter more fully apparentas reference is had to the accompanying drawings wherein my invention isillustrated and in which Figure 1 is a top elevation of a rail'truckequipped with myinvention and having one end of the bolster broken awayfor explanatory purposes,

Figure 2 is a side elevation of the truck of Figure 1,

Figure 3 is a vertical section taken along the line 3-3 of Figure 1,showing one form of bolster spring assembly,

Figure 4 is a view similar to Figure 3 showing a modified form ofbolster spring assembly,

Figure 5 is a top elevation of Figure 3,

Figure 6 is a view similar to Figures 3 and 4 showing a further modifiedform of bolster spring assembly,

Figure 7 is a top elevation of the bolster and spring assembly of Figure6, and

Figure 8 is a view similar to Figure 7 showing a modified form of springrockers.

More particularly the numeral 1 designates the wheels of a rail vehiclewhich support the axles 2. The axles 2 reside in axle housings 3 whichform the main cross-. members of the frame of the truck. The side rails4 connect the axle housings 3, each side rail 4 being rigidly connectedat one end 5 to an axle housing 3 while its other end 6 is clamped abouta rubber ring 7 encircling wheel may be depressed or elevated withrespct to the other three wheels.

The truck thus far described forms no part of the invention and hencemay be of any conventional or special type, the only requirement beingthat it have side rails or side frames of some type which may supportbolster springs and friction snubbers.

The bolster 8 is supported on the side rails 4 by means of a springassembly at each end thereof. As illustrated in Figure 3 the springassemblies are each composed of a mass of rubber 9 of essentiallycylindrical exterior shape which may be hollowed out at 10 to permit ofgreater deflection. A cap 11 fits over the top of the rubber 9 and asimilarly shaped cap 11 fits over the lower end thereof. Each cap is inthe shape of a cup with a low side wall 12 extending upwardly from amajor portion of the base and a higher side wall 13 extending throughoutthe remaining portion of the periphery of the base. The side walls 13each extend for a height such that they cover at least half the heightof the rubber spring 9, and, preferably, slightly more than one half. Arocker 17 is fixed on the base of each cup 11, outwardly thereof, forcontact with the bolster 8 and a side rail 4, respectively.

The rubber spring 9 is enlarged at each end 15 so that as the spring isloaded vertically it expands and fills the cup, generally to the lowerside walls 12. The spring 9 may also be enlarged at its midsection forcontact by the side walls 13 of the cups 11 but since there will be somefriction I prefer to use a replaceable belt 16 at the midportion of thespring 9.

In order to limit the movement of the bolster longitudinally of the siderails 4 I provide heavy brackets 18 which rise from the side rails 4 andwhich have pockets 20 to receive friction elements 19. The side walls ofthe ends of the bolster 8 are flattened at 21, as best seen at the lowerside of Figure 1, for contact with the elements 19, the brackets andelements being so spaced that there is but slight clearance between theside walls 21 and the elements 19. Thus, if the truck frame is underacceleration or deceleration with respect to the bolster, while thebolster is swinging, there will be friction damping or snubbing bytherubbing of the surfaces 21 against the elements 19. If the surfaces 21are set with very slight clearance, or with no clearance, with respectto the elements 19, then slight relative acceleration or decelerationwill result in snubbing but as the elements 19 wear in operation theclearance gradually increases and the resultant snubbing action woulddecrease if the springing means were merely coiled sprmgs.

The operation is as follows: as the bolster 8 swings it will cause thespring assemblies to rock on the rockers 17 thus causing the springs totilt. The ends of the bolster will thus be deflected from their normalswinging path and will contact the friction elements 19. The force ofthe swinging bolster may thus be said to be broken into two components,one of which is in a direction longitudinally of the side rails. Thegreater the swing of the bolster,

forming an acute angle with each other.

the greater will be the tilting'of' the spring assemblies and, hence,the. greater the. longitudinal component of the force which causesfrictional contact of the bolster and snubbers. Furthermore, it may benoted that it is conventional. to. provide stops 29- which limit theswinging movement of a bolster but it seems self-evident thatimprovement in riding quality will result if the springs themselvesgradually but rapidly increase their resistance to swinging of thebolster. Increased resistance in this invention is provided by the sideWalls 13 of the cups 11. Assume that the. bolster 8 of Figure 3 swingsto the right. The side walls 13 then resist deflecting movement of thespring 9 because the rubber 9 is placed under compression. And as afurther feature, the rubber 9, being squeezed between the side Walls 13will tend to elevate the body against gravity thus adding resistance toswinging of the bolster in the same manner as does a swing link.

Now, if the end of the bolster illustrated in Figure 3 1s swung to theleft from the position shown in Figure 3, the side walls 13 swing awayfrom the rubber thus allowmg greater softness of action of the spring 9on the side ofthe bolster awayfrom the direction of swing.

It will thus be seen that swinging of the bolster results in adisplacement ofthe ends of the bolster so that they will contact thefriction elements 19, the pressure of the contact increasing withincreasing swinging of the bolster. And it is also seen that thesupporting spring 9 stiffens at the. side of the truck towards whichswinging occurs, in such manner that the stiffening effect increaseswith increasing swinging of the bolster. And, furthermore, that thestiffening of the spring at one end of the bolster without acorresponding stiffening of the spring at the other end causes a slighttilting of the bolster which may be called banking the bolster so thatan occupant of thecar body supported by the bolster will be less awareof the swinging movement.

The spring assembly illustrated in Figure 3 permits of a. wide. range.of engineering choice in its design. The rockers 17 are illustrated asbeing set at an angle of about 45 with respect to the direction ofswing. That may be altered. as experience and desired results show thatother angularities are preferred. The rockers may be, set parallel, 'topand bottom, or out ofparallel, and the extent to which the. long sidewalls 13 envelop the sprlngs 9. may be varied to vary the amount ofstiffening accomplished.

In addition to. the above variations, the rockers. 17 at opposite sidesof the truck are shown in Figure. 1 as When this is done the bolsterrotates about its center. If the rockers are. all parallel then swingingof the bolster will. cause bodily fore. and aft displacement of thebolster with. respect. to the siderails. In the. first instance, thebolster will contact diagonallyopposite friction elements, where: as, inthe second. case, it will contact friction elements on'the same side ofthe bolster.

Figure 4 illustrates a modified form of the spring. assembly of Figure 3in that a coil spring 20 is. added. The spring 27 contacts the bolster8a directly thus enveloping the upper. spring cap 11a. Thev lower end ofthis spring is supported by a plate 28 atop thesiderail 4a, the lowerrocker 17a rocking on the. plate. 28 so that the spring 27 also envelopsthe lower spring cap 11a. By addition of this. coil spring 27 the rubberspring 9a may be partially or entirely unloaded when the vehicle isunloaded and standing idle. This spring offers some resistance toswinging of the bolster otherwise the operation is essentially the sameas described in connection with Figure 3.

Figures 6 and 7 illustrate a modification ofthe spring assembly ofFigures 3 and 4 in which the rubber spring 9b and the spring caps 11bare essentially the same as the spring 9 andthe spring caps 11 of Figure3. The caps 11b are'fixedly secured to the plates 22 which extendoutwardly beyond the base of the caps 11b to form upper and lowerseatsfor. the coil spring 200. The plates 22 are each provided with twohalf rockers 23 and 24 which radiate from the center of the plate 22.

In operation, when the bolster 8b swings to the right, Figures. 6. and7, the springs 91) and the springs 2.7a deflect until the cap side walls13b contact the rub bersprings 9b whereupon the springs 9b at the rightend of the. bolster stiifen. The spring assemblies willrock on, theleftrockers 23 at the right end of the bolster and on. the samerockers.23,at the. left end of the bolster thus deflecting the bolster,toward'friction pads on the sameside of the bolster (away from thebottom of the page asviewed in Figure 7-). When the bolster 8b thenswingsto the left, as it crosses its center position, the right end ofthe bolster will rock on the rockers 24 and the left end will dolikewise thus keeping the pressure against the same friction elements.Again, it is to be noted that I contemplate that the rockers 23. and 24of the top plate 22 are parall l, respectively, with rockers 23 and 24of the lower plate 22 but this need not be so, in fact, only one set ofrockers 23. and 24 may be used as preferences in operatingcharacteristics'and evaluation of riding quality of a vehicle becomematters of opinion in actual practice. Also, it will be noted in Figures6 and 7 that the coil spring 27a. rocks with the rubber spring 917Whereas in Figure 4 the coil spring 20 does not rock. This, again, is amatter of choice, they resistance of the springs laterally beingdesigned and computed to provide a combined resistance as may bedesired.

In Figure 8 the spring assembly is exactly the same as in Figures 6 and7 with the exception that the rockers 25 and 26, corresponding to therockers 23 and 24, do not meet at the center 0 of their respectivespring caps: 22a but at some point off-center, as illustrated. Theeffect of this is that when the bolster 8c swings to the right therubber springs and the coil springs will deflect. as previouslydescribed, and the plates 22:: at the right end of the bolster will rockon the rockers 25 while the plates 22a at the left end of the bolsterwill also rock on the rockers 25. Since the rockers 25 do not passthrough the center of the plate 22a there will be a slight lifting ofthe right end of the bolster with a corresponding slight depression ofthe left end of the bolster, by reason of the greater softness of therubber spring at the left end, thus simulating the effect of elevatingthe out-swinging side of the vehicle body carried by the bolster as isdone by swing links. As the bolster reverses its direction of swingingand as it passes through its center position the right end of thebolster will cause the plates 22a to rock on therockers 26 and the leftend to rock on their rockers 26 also.

Various changes may be made and various combinations, of the featuresillustrated may be arranged to accommodate the invention to varioustypes of service. and I therefore desire to be extended protection asdefined by the scope of the appended claims.

I claim:

1. A bolster spring assembly for supporting each end of a truck bolstercomprising a mass of rubber and a spring cap overlying at least one endthereof, said rubber being adapted to resist vertical loading by thebolster largely by compression and to resist lateral deflections largelyby shear and bending, said spring cap being composed ofa base and sidewalls extending from the periphery of said base along the length of saidspring, said side walls, having greater height over a portion of thebase than over the remainder thereof, said rubber when in staticposition having clearance with said side walls, said side walls ofgreater height contacting said rubber when said rubber is deflectedlaterally in one direction but notwhen the rubber is deflected in theoppositedirection thereby changing thecharacteristics of said rubberspring under lateral swinging movements of the bolster dependent upon'its'direction ofswinging, said spring cap having a rocker securedthereto separating said cap from its supporting surface, said rockerbeing angularly disposedv with respect to the direction of the forceswhich impose lateral loading on said rubber whereby said rubber and saidcap are caused to rock at an angle with respect tov the.

direction of swing of the bolster.

2. A bolster spring assembly for supporting each end of arail truckbolster comprising a mass of rubber and a spring cap overlying each endof said rubber, said rubber being of generally cylindrical form adaptedto resist vertical loading largely by compression, said spring caps eachhaving high side walls extending alongside less than of the periphery ofsaid rubber, the high side walls ofone ofsaid caps being diametricallyopposite the high side walls of the other of said caps, said rubber whendeflected in one direction resisting largely by a combination of shearand. bending and when deflected inthe opposite direction contacting saidhigh side walls thereby resisting lateral deflection by a combination ofcompression, shear and "bending, both of said caps having rockersoutwardly thereon separating said caps from their supporting andsupported surfaces, said-rockers being deposed at an angle with respectto the direction of the lateral forces on said spring assembly wherebythe bolster is deflected from its normal path of swinging movements.

3. A bolster spring assembly for supporting each end of a rail truckbolster comprising a mass of rubber and a spring cap overlying each endof said rubber, said rubber being of generally cylindrical form adaptedto resist vertical loading largely by compression, said spring caps eachhaving high side walls extending alongside less than 180 of theperiphery of said rubber, the high side walls of one of said caps beingdiametrically opposite the high side walls of the other of said caps,said rubber when deflected in one direction resisting largely by acombination of shear and bending and when deflected in the oppositedirection contacting said high side walls thereby resisting lateraldeflection by a combination of compression, shear and bending, both ofsaid caps having pairs of rockers outwardly thereon, said pairs ofrockers each being composed of two non-parallel rockers extendingpartially across the base of each of said caps, said rockers being soarranged with respect to the direction of the lateral deflecting forcesimposed on said spring assembly that said caps rock on one rocker ofeach pair when the force is in one direction and on the other rockers ofsaid pairs when the force is in the opposite direction.

4. A bolster spring assembly for supporting each end of a rail truckbolster comprising a mass of rubber and a spring cap overlying each endof said rubber, said rubber being of generally cylindrical form adaptedto resist vertical loading largely by compression, said spring caps eachhaving high side walls extending alongside less than 180 of theperiphery of said rubber, the high side walls of one of said caps beingdiametrically opposite the high side walls of the other of said caps,said rubber when deflected in one direction resisting largely by acombination of shear and bending and when deflected in the oppositedirection contacting said high side walls thereby resisting lateraldeflection by a combination of compression, shear and bending, both ofsaid caps having pairs of rockers outwardly thereon, said pairs ofrockers each being two non-parallel rockers which meet at a point offthe center of the base of their cap, said rockers being so positionedwith respect to the direction of the lateral deflecting forces imposedon said spring assembly that said caps rock on one rocker of each pairwhen the force is in one direction and on the other rocker of each ofsaid pairs when the force is in the opposite direction.

5. In a rail truck, a truck frame comprising side rails and crossmembers, spring assemblies supporting each end of said bolster from saidside rails, each of said assemblies comprising a rubber spring ofgenerally cylindrical shape having a spring cap on each end thereof,said spring caps each having high side walls arising from a portion oftheir periphery not to exceed 180, the side walls of said caps beingoppositely arranged with respect to said spring and so arranged withrespect to said bolster that when said bolster swings laterally of thetruck the spring at the end of the bolster leading the swing contactssaid side walls thereby stiffening that spring against increasedswinging of said bolster, said spring caps having rockers outwardlythereof for contact with said bolster and said side rails respectively,said rockers being angularly disposed with respect to the center line ofsaid bolster whereby said spring assemblies tilt during swinging of saidbolster to deflect said bolster out of its normal path of swing, andfriction pads carried by each of said cross members for frictionalcontact with said bolster when said spring assemblies tilt.

References Cited in the file of this patent UNITED STATES PATENTS416,555 Black Dec. 3, 1889 578,305 Baines Mar. 2, 1897 1,936,389Hallquist Nov. 21, 1933 2,015,025 Barrows Sept. 17, 1935 2,216,231Dentler Oct. 1, 1940 2,406,199 Clasen Aug. 20, 1946 2,492,337 TravillaDec. 27, 1949 2,524,914 Lehman Oct. 10, 1950 2,535,197 Dath Dec. 26,1950 2,573,108 Piron Oct. 30, 1951 2,590,033 Piron Mar. 18, 19522,601,981 Lehrman July 1, 1952 FOREIGN PATENTS 487,468 Great BritainJune 21, 1938

